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1.
本文使用相对论组态相互作用方法计算了0.1E1≤kTe≤10E1(E1是类钠钨离子的第一电离能E1=7129.5 eV)温度范围内类氖W64+离子基态双电子复合(DR)速率系数.类氖W64+离子基态DR过程需要考虑(2s2p)73ln′l′,(2s2p)74l4l′以及(2s2p)74l5l′双激发自电离组态.对于(2s2p)73ln′l′双激发自电离组态,轨道角量子数l′>8的(2s2p)73ln′l′组态对双电子复合速率系数的贡献可以忽略不计;(2s2p)73ln′l′组态双电子激发自电离态的高里德堡态对双电子复合速率系数的贡献满足n′-3组态-组态外推法.对细致计算得到的类氖W64离子基态DR总速率系数进行了拟合,得到W64+离子基态在0.1E1≤kTe≤10E1温度范围内的总DR速率系数随电子温度变化的经验公式.  相似文献   

2.
利用基于全相对论组态相互作用理论的FAC程序包,详细研究了类硒W40+离子从基组态3s23p63d104s24p4俘获一个电子形成双激发态(3s23p63d104s24p4)-1 nln′l′(n=4~6,n′=4~100)的双电子复合(DR)过程.通过对不同壳层电子激发的DR速率系数的比较,得到了主要的电子激发DR通道,并且发现由4p电子激发的DR速率系数对总DR速率系数有重要贡献.在1~5×104 eV温度范围内,计算得到了n′=4~16的DR速率系数,并外推到n′=100,进而得到总DR速率系数.给出了Δn=0,1,2三类芯激发对总DR速率系数的贡献,发现对总DR速率系数的主要贡献来自于Δn=0,1的芯激发.对总DR速率系数和辐射复合(RR)以及三体复合(TBR)速率系数进行了比较,发现DR速率系数在研究的温度范围内远大于TBR和RR速率系数.为了方便应用,对总DR速率系数进行了参数拟合.  相似文献   

3.
基于全相对论组态相互作用理论,详细计算了类铑钆离子的双电子复合(DR)速率系数;研究分析了内壳层电子激发、辐射通道和级联退激对DR速率系数的影响,以及DR速率系数随高n电子轨道角动量的变化.结果表明,内壳层4p电子激发以及级联退激对DR速率系数的贡献不可忽略.对双电子复合、辐射复合以及三体复合速率系数做了比较,在温度大于1eV时,双电子复合速率系数都大于辐射复合和三体复合速率系数,相应的DR过程对于等离子体离化态分布和能级布居以及光谱模拟都极为重要.同时,对基态和第一激发态的DR速率系数进行了参数拟合.  相似文献   

4.
基于相对论多组态HF程序,采用畸变波理论和独立共振近似,计算了0.1~9.0keV温度范围的类锂高电荷离子Hf^69+,Ta^70+,W^71+和Re^72+对应于原子实△n=0,1激发的态-态双电子复合速率系数,讨论了复合速率系数随电子温度,原子序数,复合类型以及双激光发态中俘获电子的主量子数的变化关系,计算结果表明,不同复合通道的速率系数存在的很大差异,由此提出了通过双电子复合过程来实现高电荷  相似文献   

5.
使用相对论组态相互作用方法计算类氦I离子的KLn双电子共振强度、速率系数.双电子复合共振强度随着n的增加迅速降低.对于同一个双激发态,通过内壳层衰退的双电子复合共振强度和速率系数高于通过外壳层衰退的双电子复合共振强度和速率系数.通过内壳层2p电子辐射衰退的通道1s2pnl-1s2nl是最主要的KLn双电子复合辐射衰退通道.1s2pnl-1s2nl辐射衰退通道中对双电子复合速率系数贡献最大的是1s2p2-1s22p辐射衰退通道.1s2p2-1s22p辐射衰退通道的双电子复合速率系数占1s2pnl-1s2nl辐射通道速率系数的70%.  相似文献   

6.
使用相对论组态相互作用方法计算了电子温度在0.01EI≤kTe≤10EI(EI=3332eV,是类钠Xe43+离子的第一电离能)范围内基态类氖Xe44+离子的双电子复合(DR)速率系数。对类氖Xe44+离子基态DR过程贡献最大的是(2s2p)73ln′l′双激发自电离组态,对总DR速率系数的贡献略大于90%,其中最主要的贡献来自(2s2p)73l3l′,(2s2p)73l4l′组态,占总速率系数的70%以上。对于通过(2s2p)73ln′l′类钠氙离子双激发自电离组态的双电子复合过程,l′>8的贡献可以忽略,n′>12的贡献满足n′-3组态-组态外推法则。  相似文献   

7.
利用基于多组态Driac-Fock(MCDF)理论方法发展的程序包GRASP及FAC程序包,详细计算了共振双激发态1s2l2l′的共振能量、自电离速率、辐射速率及双电子复合截面.重点讨论了Breit相互作用对类氦钨离子双电子复合截面的影响.  相似文献   

8.
利用全相对论组态相互作用理论方法,研究了Au33+离子由基态俘获一个电子形成双激发态(3d104s24p64d10)-1nln'l'(n=4~6,n'=4~15)的双电子复合(DR)过程。分析考虑了双激发态j=4d94f15p级联辐射退激到末态f=4d94fn'l'(n'=9,12.l'=0,2),可知DAC效应对DR速率系数有不可忽略的影响。研究分析了4d电子激发到不同壳层的DR速率系数以及在综合了分析得到对Au33+离子DR过程有明显贡献的各种因素后,进一步得到了总DR速率系数。  相似文献   

9.
基于全相对论组态相互作用理论的(FAC程序包,详细计算了类铷等电子序列离子双激发态(4s~24p~64d~1)-1nln'l'n=4,5,6,n',≤23,l'≤12)7个离子(Sb~(14+),Te~(15+),Xe~(17+),Tb~(28+),Hf~(35+),W~(37+),Au~(42+))的双电子复合(Dielectronic reombination DR)速率系数,并用能级到能级的方法外推到n'=1 000.分别研究了激发通道和辐射通道、共振稳态跃迁(RS)和非共振稳态跃迁以及辐射跃迁到可自电离态及随后的级联退激(,DAC)对DR速率系数的贡献,分析了各种效应随着原子序数(Z)的变化规律.研究表明RS+NRS随着Z的增大对速率系数的影响越来越大,而DAC的贡献随着Z的增大越来越小,对于Au~(42+)离子(Z=79),其贡献在,50 000 eV处最大,达到14.36%,仍不可忽略.最后,总结了这7个离子总的DR速率系数的规律.为了便于使用对7个离子总的DR速率系数进行了参数拟合,得到了适用于类铷等电子序列的适用于中高温区域的一个经验拟合公式.  相似文献   

10.
基于全相对论组态相互作用理论的FAC程序包,详细计算了类铑等电子序列10个离子(Sn~(5+),Sb~(6+),Te~(7+),Xe~(9+),Gd~(19+),Tb~(20+),W~(29+),Re~(30+),Au~(34+),Tl~(36+))的双电子复合(Dielectronic recombination, DR)速率系数,研究了激发通道和辐射通道,共振稳态跃迁、非共振稳态跃迁和辐射跃迁到可自电离态及随后的级联退激对双电子复合的贡献,分析了各种效应随原子序数的变化规律.结果表明,级联退激的贡献随着原子序数的增大越来越小,至Tl~(36+)离子(Z=81),其贡献在4 000 eV处有19.98%,仍不可忽略.仅考虑共振稳态跃迁和非共振稳态跃迁贡献计算值与又考虑了级联退激贡献计算值的偏差在13.40%以内.为了方便使用,对得到的总DR速率系数进行了参数拟合.并且总结了总的DR速率系数的规律,得到了适用于类铑等电子序列中高温处的一个经验拟合公式.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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